img name is $user->id.jpg or 543.jpg
<?php
$logo = "<img src='images/jbjobs/$user->id.jpg'>";
?>
after here
$logo = "<img src='images/jbjobs/
I dont know what to do and I have to escape ' or ".
Try
<?php
$logo = "<img src='images/jbjobs/{$user->id}.jpg'>"; // {} is like concatenate
?>
Any of the following will do:
$logo = "<img src='images/jbjobs/{$user->id}.jpg'>";
$logo = "<img src='images/jbjobs/".$user->id.".jpg'>";